Fan-Out Package and Methods of Forming Thereof

ABSTRACT

An embodiment is a structure including a molding compound laterally encapsulating a chip with a contact pad. A first dielectric layer is formed overlying the molding compound. A first metallization layer is formed overlying the first dielectric layer, in which the first metallization layer extends through the first dielectric layer to contact the contact pad. A second dielectric layer is formed overlying the first metallization layer and the first dielectric layer. A second metallization layer is formed overlying the second dielectric layer and extends through the second dielectric layer to contact the first metallization layer.

PRIORITY CLAIM AND CROSS-REFERENCE

This application is a continuation of U.S. patent application Ser. No.14/322,842, filed on Jul. 2, 2014, entitled “Fan-Out Package and Methodof Forming Thereof,” which application claims the benefit of U.S.Provisional Application No. 61/928,836, filed on Jan. 17, 2014, entitled“Method and Apparatus for Packaging Semiconductor Dies,” whichapplications are hereby incorporated herein by reference in theirentirety.

BACKGROUND

Semiconductor devices are used in a variety of electronic applications,such as personal computers, cell phones, digital cameras, and otherelectronic equipment, as examples. Semiconductor devices are typicallyfabricated by sequentially depositing insulating or dielectric layers,conductive layers, and semiconductive layers of material over asemiconductor substrate, and patterning the various material layersusing lithography to form circuit components and elements thereon.Dozens or hundreds of integrated circuits are typically manufactured ona single semiconductor wafer. The individual dies are singulated bysawing the integrated circuits along a scribe line. The individual diesare then packaged separately, in multi-chip modules, or in other typesof packaging, for example.

The semiconductor industry continues to improve the integration densityof various electronic components (e.g., transistors, diodes, resistors,capacitors, etc.) by continual reductions in minimum feature size, whichallow more components to be integrated into a given area. These smallerelectronic components such as integrated circuit dies may also requiresmaller packages that utilize less area than packages of the past, insome applications.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present embodiments, and theadvantages thereof, reference is now made to the following descriptionstaken in conjunction with the accompanying drawings, in which:

FIGS. 1 through 8 are various cross sectional views of structures duringa manufacturing process according to an embodiment.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The making and using of the present embodiments are discussed in detailbelow. It should be appreciated, however, that the present disclosureprovides many applicable inventive concepts that can be embodied in awide variety of specific contexts. The specific embodiments discussedare merely illustrative of specific ways to make and use the disclosedsubject matter, and do not limit the scope of the different embodiments.

Embodiments will be described with respect to a specific context, namelya fan-out package structure. Other embodiments may also be applied,however, to other package structures. Figures and discussion belowillustrate simplified structures so as to not obscure various featuresand omit redundant features that would be apparent to a person ofordinary skill in the art. Like reference numbers in the figures referto like components. Although method embodiments may be described asbeing performed in a particular order, other embodiments may beperformed in any logical order.

FIGS. 1 through 8 illustrate various cross sectional views of structuresduring a manufacturing process according to an embodiment.

FIG. 1 illustrates two chips 10 adhered to a carrier substrate 200 by anadhesive film 202. In an embodiment, the chips 10 are formed as part ofa wafer, and the wafer is then singulated to form individual chips 10.The chips 10 may be, for example, a logic integrated circuit, a memorydie, an analog die, or any other die. The chips 10 each includes asubstrate 12, a contact pad 14 on the substrate 12 and a passivationlayer 16 overlying the substrate 12 and the contact pad 14. Thesubstrate 12 may include a semiconductor substrate, such as a bulksemiconductor substrate, semiconductor-on-insulator substrate, or thelike, on which electrical circuitry including active devices, such astransistors, and/or passive devices, such as capacitors, inductors, orthe like, are formed according to semiconductor processes. Theelectrical circuitry formed in the semiconductor substrate may be anytype of circuitry suitable for a particular application. For example,the electrical circuitry may include various N-type metal-oxidesemiconductor (NMOS) and/or P-type metal-oxide semiconductor (PMOS)devices, such as transistors, capacitors, resistors, diodes,photo-diodes, fuses, and the like, interconnected to perform one or morefunctions. The functions may executed using various structures includingmemory structures, processing structures, sensors, amplifiers, powerdistribution, input/output circuitry, or the like. Other circuitry maybe used as appropriate for a given application. Dielectric layers andmetal lines are formed on the electrical circuitry. The dielectriclayers may be formed, for example, of a low dielectric constant (low-K)dielectric material, such as phosphosilicate glass (PSG),borophosphosilicate glass (BPSG), fluorinated silicate glass (FSG),SiO_(x)C_(y), Spin-On-Glass, Spin-On-Polymers, silicon carbon material,compounds thereof, composites thereof, combinations thereof, or thelike, by any suitable method, such as spinning, chemical vapordeposition (CVD), and/or plasma-enhanced CVD (PECVD). The metal linesformed of, for example, copper, tungsten, aluminum and/or alloys thereofare formed in the dielectric layers and electrically couple theelectrical circuitry together and/or to the contact pad 14.

The contact pad 14 is formed on the uppermost dielectric layer of thesubstrate 12 to electrically connect to the underlying metallizationlayers. In some embodiments, the contact pads 14 are formed of aluminum,aluminum copper, aluminum alloys, copper, copper alloys, or the like.The passivation layer 16 is formed over the top surface of the substrate12 and is patterned to form an opening 16 a exposing at least a portionof the contact pad 14. The passivation layer 16 may be a single layer ora laminated multi-layer structure. In some embodiments, the passivationlayer 16 is formed of a dielectric material, such as undoped silicateglass (USG), silicon nitride, silicon oxide, silicon oxynitride, or anon-porous material. In some embodiments, the passivation layer 16 isformed by chemical vapor deposition (CVD), physical vapor deposition(PVD), or any other suitable process.

In an embodiment, the chips 10 are placed on the carrier substrate 200using, for example, a pick-and-place tool, and the chips 10 are adheredto the carrier substrate 200 by the adhesive film 202, such as anysuitable adhesive, such as UV glue (which loses its adhesive propertywhen exposed to UV lights), or film on wire (FOW) materials. The carriersubstrate 200 may be a wafer-form substrate or a panel-form substrate.Several dozen chips 10 or several hundred chips 10 or more may beattached to the carrier substrate 200, depending on a size of the chips10, a size of carrier substrate 200, and the particular application. Thechip 10 has a first side 10F (also referred to herein as a front side10F) and a second side 10B (also referred to herein as a back side 10B).By placing the chips 10 in predetermined locations on the carriersubstrate 200, in some embodiments, a back side 10B of the chip 10 isattached to the adhesive film 202, such that the chip 10 is mountedface-up on the carrier substrate 200.

In FIG. 2, a molding compound 18 is formed at least laterallyencapsulating the chips 10. By laterally encapsulating, it is meant thatthe molding compound is formed to surround the chip(s) on all sides, butnot extending over the top surface of the chip(s). The molding compound18 is formed to fill gaps between the chips 10. The molding compound 18may be formed using compression molding, lamination, or the like. Themolding compound 18 may be an epoxy-based complex or the like. Themolding compound 18 may be cured using, for example, a constanttemperature or a ramped temperature thermal process at a temperaturebetween about 120° C. and about 340° C. The molding compound 18 mayinitially cover, i.e. extend over to top surface of, chips 10 as formed,and then undergo a grinding process to expose a sacrificial layer (notshown) over the chips 10. The sacrificial layer may be removed using asolvent, chemicals, or the like. In an example, a wet etch selective tothe sacrificial layer, such as a dilute KOH solution that is, forexample, about 3% to about 5% KOH, is used to remove the sacrificiallayer. In some embodiments, the front sides 10F of chips 10 are notcovered by the molding compound 18, such that the contact pads 14 andthe passivation layers 16 are exposed. In an embodiment, the top surfaceof the passivation layer 16 is lower than the top surface of the moldingcompound 18. In some embodiments, the top surface of the passivationlayer 16 is substantially level with the top surface of the moldingcompound 18.

Referring to FIG. 3, a first dielectric layer 30 is formed over thepassivation layers 16 and contact pads 14 of the chips 10 and over themolding compound 18. In some embodiments, the first dielectric layer 30includes a polybenzoxazole (PBO) layer, a polyimide layer, abenzocyclobutene (BCB) layer, an epoxy layer, a photo-sensitive materiallayer, other suitable polymer materials, or a combination thereof. Thefirst dielectric layer 30 can be deposited by a spin coating process,laminating process, the like, or a combination thereof. Then the firstdielectric layer 30 is patterned by photolithography and/or etchingprocesses to form openings 30 a, through which the underlying contactpads 14 are exposed. In at least some embodiments, the opening 30 a ispositioned over the opening 16 a of the passivation layer 16. In theillustrated embodiment, the dimension (e.g. diameter) of opening 30 a isless than that of opening 16 a. The dimension of the opening 30 a may belarger than or equal to that of the opening 16 a, in other contemplatedembodiments.

In FIG. 4, a first metallization layer 32 is formed on the firstdielectric layer 30 as various traces, and the first metallization layer32 fills the openings 30 a to form a plurality of first via connections34 directly over a respective contact pad 14. In some embodiments, thefirst via connection 34 (when viewed from a “top down” view) can be aring shape, a ring-like shape, a rectangular shape, a square-like shape,a triangular shape, a hexagonal shape, an octagonal shape, or the like.Also, the first via connection 34 may be an enclosed shape, broken ordisconnected shape. In an embodiment, the first metallization layer 32includes a first seed layer 32 a and a first conductive layer 32 b. Forexample, the first seed layer 32 a is deposited over the firstdielectric layer 30, lining the bottom and sidewalls of the openings 30a of the first dielectric layer 30. The first seed layer 32 a can becopper, titanium, titanium, titanium nitride, titanium nitride, acombination of copper and titanium (Ti/Cu), the like, or a combinationthereof deposited by atomic layer deposition (ALD), sputtering, anotherphysical vapor deposition (PVD) process, or the like. The conductivelayer 32 b is formed on the first seed layer 32 a and fills the openings30 a of the first dielectric layer 30. The first conductive layer 32 bcan be copper, copper alloys, aluminum, aluminum alloys, tungsten,tungsten alloys, or combinations thereof, formed by a plating process,such as electroless plating, electroplating, or the like. In anembodiment, a copper plating process is performed by modifying additiveselection and controlling concentration of copper solution, such thatthe surface of the first conductive layer 32 b in the opening 30 a formsa flat metal surface 32 s. For example, the copper plating process isperformed at a plating rate greater than about 1 μm/min. The firstconductive layer 32 b formed in the opening 30 a has a width W and aheight H. For example, the height H is less than 10 μm. The height H maybe about 3 μm. In an embodiment, the ratio of W/H is greater than about2. In another embodiment, the ratio of W/H is less than about 20. Instill another embodiment, the ratio of W/H is between 2 and 20. Next,photolithography and etching processes are performed to pattern thefirst conductive layer 32 b and the first seed layer 32 a so as to formthe pattern for the first metallization layer 32 that is desired. Thefirst metallization layer 32 is a post-passivation interconnect (PPI)structure which can function as interconnection layers, power lines,re-distribution lines (RDL), inductors, capacitors or any passivecomponents.

In FIG. 5, a second dielectric layer 40 is formed over the firstdielectric layer 30 and the first metallization layer 32. In someembodiments, the second dielectric layer 40 includes a polybenzoxazole(PBO) layer, a polyimide layer, a benzocyclobutene (BCB) layer, an epoxylayer, a photo-sensitive material layer, other suitable polymermaterials, or a combination thereof. The second dielectric layer 40 canbe deposited by a spin coating process, laminating process, the like, ora combination thereof. Then the second dielectric layer 40 is patternedby photolithography and/or etching processes to form openings 40 a,through which portions of the underlying first metallization layer 32are exposed. In at least some embodiments, the first via connection 34is exposed by the opening 40 a because the opening 40 a is positionedover the opening 30 a of the first dielectric layer 30. For example, thedimension of the opening 40 a is substantially equal to that of theopening 30 a. The dimension of the opening 40 a may be larger than orless than that of the opening 30 a

Next, as shown in FIG. 6, a second metallization layer 42 is formed onthe second dielectric layer 40 as various traces or landing pads, andthe second metallization layer 42 is formed in the openings 40 a to forma plurality of second via connections 44 directly over a respectivefirst via connection 34. In some embodiments, the second via connection44 is a ring shape, a ring-like shape, a rectangular shape, asquare-like shape, a triangular shape, a hexagonal shape, an octagonalshape, or the like. Also, the second via connection 44 may be anenclosed shape, broken or disconnected shape. In an embodiment, thesecond metallization layer 42 includes a second seed layer 42 a and asecond conductive layer 42 b. For example, the second seed layer 42 a isdeposited over the second dielectric layer 40, lining the bottom andsidewalls of the openings 40 a of the second dielectric layer 40. Thesecond seed layer 42 a can be copper, titanium, titanium, titaniumnitride, titanium nitride, a combination of copper and titanium (Ti/Cu),the like, or a combination thereof deposited by atomic layer deposition(ALD), sputtering, another physical vapor deposition (PVD) process, orthe like. The second conductive layer 42 b is formed on the second seedlayer 42 a. The second conductive layer 42 b is also formed in theopenings 40 a of the second dielectric layer 40. The second conductivelayer 42 b may partially fill the opening 40 a (as shown in FIG. 6) orcompletely fill the opening 40 a (not shown) depending on the openingsize and plating process control. The second conductive layer 42 b canbe copper, copper alloys, aluminum, aluminum alloys, tungsten, tungstenalloys, or combinations thereof, formed by a plating process, such aselectroless plating, electroplating, or the like. Next, photolithographyand etching processes are performed to pattern the second conductivelayer 42 b and the second seed layer 42 a so as to expose the patternfor the second metallization layer 42 that is desired. The secondmetallization layer 42 includes the second via connection 44electrically coupled to the first via connection 34. The secondmetallization layer 42 can function as interconnection layers, powerlines, re-distribution lines (RDL), inductors, capacitors or any passivecomponents. While via connection 44 is shown as being vertically alignedwith via connection 34, other arrangements, such as via connection 44being offset from via connection 34, are within the contemplated scopeof the present disclosure.

Referring to FIG. 7, bumps 50 are formed on the second metallizationlayer 42. In an embodiment, the bumps 50 are solder bumps, for example,including lead-free solder, SnAg, or a solder material including alloysof tin, lead, silver, copper, nickel, bismuth, or combinations thereof.The solder bumps may be formed by placing solder balls or plating asolder layer with a reflowing process. In some embodiments, the bump 50is a copper pillar bump, a metal bump including nickel or gold, orcombinations thereof. In an embodiment, each of the bumps 50 has adiameter greater than about 200 μm. Then a protection layer 52 isoptionally formed over the second metallization layer 42 and the seconddielectric layer 40 and around a portion of the bumps 50. For example,the top portions 50 a of the bumps 50 are exposed and extend above theprotection layer 52. In an embodiment, the protection layer 52 is abracing material which is molding compound or the like that providesstructural support.

Next, as shown in FIG. 8, the carrier substrate 200 is detached from thechips 10 and the molding compound 18, and then the resulting structureis sawed into a plurality of individual packages also referred to asfan-out packages. In an embodiment, a tape 204 is provided on theadhesive film 202 covering the back side 10B of the chips 10 and thebackside of the molding compound 18. The fan-out package includes one ormore than one chips 10 and two metallization layers 32 and 42 over thefront side 10F of the chip 10, in which a stacking via structure 54including the second via connection 44 and the first via connection 34are positioned over and electrically coupled to the contact pad 14 ofthe chip 10. As shown, the first via connection 34 is formed in theopening 30 a of the first dielectric layer 30. The first via connection34 includes the first seed layer 32 a lining the bottom and sidewall ofthe opening 30 a and the first conductive layer 32 b filling the opening30 a. The top surface of the first via connection 34 includes a flatmetal surface according to an embodiment. The second via connection 44is formed in the opening 40 a of the second dielectric layer 40. Thesecond via connection 44 includes the second seed layer 42 a lining thebottom and sidewall of the opening 40 a and the second conductive layer42 b in the opening 40 a. The second via connection 44 is formed overthe first via connection 34 such that the second seed layer 42 a issandwiched between the first conductive layer 32 b and the secondconductive layer 42 b. By modifying the plating rate for the firstconductive layer 32 b and forming the ratio of W/H of the firstconductive layer 32 b, a flat metal surface can be formed on the firstvia connection 34 and a thickness gap between the molding compound 18and the first dielectric layer 30 can be minimized, and therefore aphotolithographic window for the second dielectric layer 40 is enlargedand a fine-pitch fan-out package is achieved. Additionally, costs may bereduced using some embodiments.

One embodiment is a structure including a chip including a substrate anda contact pad on the substrate. A molding compound laterallyencapsulates the chip with none of the molding compound being verticallyaligned with the chip. A first dielectric layer overlies the moldingcompound and the chip. The structure further includes a firstmetallization layer having a first portion and a second portion, thefirst portion of the first metallization layer overlying the firstdielectric layer and the second portion of the first metallization layerextending through the first dielectric layer electrically coupled to thecontact pad. The second portion of the first metallization layer has aflat top. A second dielectric layer overlies the first metallizationlayer and the first dielectric layer. The structure further includes asecond metallization layer having a first portion and second portion,the first portion of the second metallization layer overlying the seconddielectric layer and the second portion of the second metallizationlayer extending through the second dielectric layer electrically coupledto the first metallization layer. The second portion of the secondmetallization layer is vertically aligned with the second portion of thefirst metallization layer.

Another embodiment is a structure that includes a chip including asubstrate and a contact pad on the substrate, where the contact pad iscovered by a chip passivation layer. The structure also includes amolding compound laterally encapsulating the chip. A first dielectriclayer overlies the molding compound and the chip. The structure furtherincludes a first metallization layer having a first portion and a secondportion, the first portion of the first metallization layer overlyingthe first dielectric layer and the second portion of the firstmetallization layer extending through the first dielectric layer and thechip passivation layer. The second portion of the first metallizationlayer has a first lateral interface and a second lateral interface withthe first dielectric layer. The second portion of the firstmetallization layer has a flat top from the first lateral interface tothe second lateral interface. The structure further includes a seconddielectric layer overlying the first metallization layer and a secondmetallization layer having a first portion and a second portion. Thefirst portion of the second metallization layer overlies the seconddielectric layer and the second portion of the second metallizationlayer extends through the second dielectric layer and contacts the firstmetallization layer. The second portion of the second metallizationlayer does not extend into the first dielectric layer.

A further embodiment is a structure including a chip with a contact padand a molding compound surrounding sides of the chip. The structurefurther includes a passivation layer overlying the contact pad, thepassivation layer having sidewalls which interface with the moldingcompound. A first dielectric layer overlies the molding compound and thepassivation layer. A first conductive layer overlies the firstdielectric layer, a first portion of the first conductive layerextending through the first dielectric layer and through the passivationlayer and contacting the contact pad. The first portion of the firstconductive layer has a width (w) and a height (h), where h is at leastas great as a thickness of the first dielectric layer adjacent to thefirst portion of the first conductive layer. The first portion of thefirst conductive layer has a flat top surface, and a ratio of w:h isgreater than 2. The structure includes a second dielectric layeroverlying the first conductive layer and the first dielectric layer anda second conductive layer overlying the second dielectric layer, where afirst portion of the second conductive layer extends through the seconddielectric layer and physically contacts the first conductive layer.

An embodiment is a package including a chip having a substrate and acontact pad on the substrate and a molding compound laterallyencapsulating the chip. A first dielectric layer is formed overlying themolding compound and the chip and has a first opening exposing thecontact pad. A first metallization layer is formed overlying the firstdielectric layer, in which the first metallization layer fills the firstopening. A second dielectric layer is formed overlying the firstmetallization layer and the first dielectric layer and has a secondopening over the first opening. A second metallization layer is formedoverlying the second dielectric layer and formed in the second opening.

Another embodiment is package including a chip having a substrate and acontact pad on the substrate, and a molding compound laterallyencapsulating the chip. A first dielectric layer is formed overlying themolding compound and the chip and has a first opening exposing thecontact pad. A first seed layer is formed overlying the first dielectriclayer and lines a sidewall and a bottom of the first opening. A firstconductive layer is formed overlying the first seed layer and fills thefirst opening. A second dielectric layer is formed overlying the firstconductive layer and has a second opening directly over the firstopening. A second seed layer is formed overlying the second dielectriclayer and lines a sidewall and a bottom of the second opening. A secondconductive layer is formed overlying the second seed layer.

A further embodiment is a method including: providing a chip with acontact pad; forming a molding compound laterally encapsulating thechip, the contact pad being exposed through the molding compound;forming a first dielectric layer over the molding compound and the chip;forming a first opening in the first dielectric layer exposing thecontact pad; forming a first conductive layer overlying the firstdielectric layer and filling the first opening, wherein the firstconductive layer in the first opening has a flat surface; forming asecond dielectric layer over the first conductive layer and the firstdielectric layer; forming a second opening in the second dielectriclayer exposing the first conductive layer over the first opening; andforming a second conductive layer overlying the second dielectric layerand physically contacting the first conductive layer through the secondopening.

Although the present embodiments and their advantages have beendescribed in detail, it should be understood that various changes,substitutions and alterations can be made herein without departing fromthe spirit and scope of the disclosure as defined by the appendedclaims. Moreover, the scope of the present application is not intendedto be limited to the particular embodiments of the process, machine,manufacture, composition of matter, means, methods, and steps describedin the specification. As one of ordinary skill in the art will readilyappreciate from the disclosure, processes, machines, manufacture,compositions of matter, means, methods, or steps, presently existing orlater to be developed, that perform substantially the same function orachieve substantially the same result as the corresponding embodimentsdescribed herein may be utilized according to the present disclosure.Accordingly, the appended claims are intended to include within theirscope such processes, machines, manufacture, compositions of matter,means, methods, or steps.

What is claimed is:
 1. A structure comprising: a chip comprising asubstrate and a contact pad on the substrate; a molding compoundlaterally encapsulating the chip, none of the molding compound beingvertically aligned with the chip; a first dielectric layer overlying themolding compound and the chip; a first metallization layer having afirst portion and a second portion, the first portion of the firstmetallization layer overlying the first dielectric layer, the secondportion of the first metallization layer extending through the firstdielectric layer electrically coupled to the contact pad, wherein thesecond portion of the first metallization layer has a flat top; a seconddielectric layer overlying the first metallization layer and the firstdielectric layer; and a second metallization layer having a firstportion and second portion, the first portion of the secondmetallization layer overlying the second dielectric layer, the secondportion of the second metallization layer extending through the seconddielectric layer electrically coupled to the first metallization layer,the second portion of the second metallization layer being verticallyaligned with the second portion of the first metallization layer.
 2. Thestructure of claim 1, wherein the second metallization layer physicallycontacts the first metallization layer.
 3. The structure of claim 1,wherein the second portion of the second metallization layer has a topsurface which is below a top surface of the first portion of the secondmetallization layer.
 4. The structure of claim 1, wherein the firstmetallization layer comprises a first seed layer and a first conductivelayer formed on the first seed layer.
 5. The structure of claim 4,wherein the first seed layer comprises titanium and the first conductivelayer comprises copper.
 6. The structure of claim 1, wherein the secondmetallization layer comprises a second seed layer and a secondconductive layer formed on the second seed layer.
 7. The structure ofclaim 6, wherein the second seed layer comprises titanium and the secondconductive layer comprises copper.
 8. The structure of claim 1, furthercomprising a bump on the second metallization layer.
 9. The structure ofclaim 8, further comprising a protection layer overlying the secondmetallization layer and the second dielectric layer and around a portionof the bump.
 10. The structure of claim 1, wherein the chip comprises apassivation layer on the substrate and covering a portion of the contactpad, and the first dielectric layer is formed overlying the passivationlayer.
 11. A structure comprising: a chip comprising a substrate and acontact pad on the substrate, the contact pad covered by a chippassivation layer; a molding compound laterally encapsulating the chip;a first dielectric layer overlying the molding compound and the chip; afirst metallization layer having a first portion and a second portion,the first portion of the first metallization layer overlying the firstdielectric layer, the second portion of the first metallization layerextending through the first dielectric layer and the chip passivationlayer, the second portion of the first metallization layer having afirst lateral interface and a second lateral interface with the firstdielectric layer, the second portion of the first metallization layerhaving a flat top from the first lateral interface to the second lateralinterface; a second dielectric layer overlying the first metallizationlayer; and a second metallization layer having a first portion and asecond portion, the first portion of the second metallization layeroverlying the second dielectric layer, the second portion of the secondmetallization layer extending through the second dielectric layer andcontacting the first metallization layer, the second portion of thesecond metallization layer not extending into the first dielectriclayer.
 12. The structure of claim 11, wherein the second portion of thesecond metallization layer has a top surface extending below a topsurface of the second dielectric layer.
 13. The structure of claim 12,wherein the first metallization layer comprises a first seed layer andfirst conductive layer, and wherein the first seed layer comprisestitanium and the first conductive layer comprises copper.
 14. Thestructure of claim 11, wherein the second metallization layer comprisesa second seed layer and a second conductive layer, and wherein thesecond seed layer comprises titanium and the second conductive layercomprises copper.
 15. The structure of claim 14, further comprising abump on the second conductive layer.
 16. The structure of claim 15,further comprising a protection layer overlying the second conductivelayer and the second dielectric layer and around a portion of the bump.17. A structure comprising: a chip with a contact pad; a moldingcompound surrounding sides of the chip; a passivation layer overlyingthe contact pad, the passivation layer having sidewalls which interfacewith the molding compound; a first dielectric layer overlying themolding compound and the passivation layer; a first conductive layeroverlying the first dielectric layer, a first portion of the firstconductive layer extending through the first dielectric layer andthrough the passivation layer and contacting the contact pad, whereinthe first portion of the first conductive layer has a width (W) and aheight (H), wherein H is at least as great as a thickness of the firstdielectric layer adjacent to the first portion of the first conductivelayer, wherein the first portion of the first conductive layer has aflat top surface, wherein a ratio of W : H is greater than 2; a seconddielectric layer overlying the first conductive layer and the firstdielectric layer; and a second conductive layer overlying the seconddielectric layer, a first portion of the second conductive layerextending through the second dielectric layer and physically contactingthe first conductive layer.
 18. The structure of claim 17, wherein thecontact pad, first portion of the first conductive layer, and firstportion of the second conductive layer are vertically aligned.
 19. Thestructure of claim 17, wherein the ratio of W:H is less than
 20. 20. Thestructure of claim 17, wherein the first conductive layer comprises afirst layer and a second layer, wherein the first layer is a seed layerunder the second layer.